diff --git a/library/debug.c b/library/debug.c
index 070f63a..4752ab1 100644
--- a/library/debug.c
+++ b/library/debug.c
@@ -42,7 +42,8 @@
 #define mbedtls_snprintf    snprintf
 #endif
 
-#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && !defined(inline)
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
 #define inline __inline
 #endif